/*
SD card read/write
This example shows how to read and write data to and from an SD card file
The circuit:
* SD card attached to SPI bus as follows:
** MOSI - pin 11, pin 7 on Teensy with audio board
** MISO - pin 12
** CLK - pin 13, pin 14 on Teensy with audio board
** CS - pin 4, pin 10 on Teensy with audio board
created Nov 2010
by David A. Mellis
modified 9 Apr 2012
by Tom Igoe
This example code is in the public domain.
*/
#include <SD.h>
#include <SPI.h>
File myFile;
// change this to match your SD shield or module;
// Arduino Ethernet shield: pin 4
// Adafruit SD shields and modules: pin 10
// Sparkfun SD shield: pin 8
// Teensy audio board: pin 10
// Teensy 3.5 & 3.6 & 4.1 on-board: BUILTIN_SDCARD
// Wiz820+SD board: pin 4
// Teensy 2.0: pin 0
// Teensy++ 2.0: pin 20
[COLOR="#FF0000"]const int chipSelect = 10; Initializes.[/COLOR]
[COLOR="#FF0000"]//const int chipSelect = BUILTIN_SDCARD; FAILS to initialize.[/COLOR]
void setup()
{
//UNCOMMENT THESE TWO LINES FOR TEENSY AUDIO BOARD:
//SPI.setMOSI(7); // Audio shield has MOSI on pin 7
//SPI.setSCK(14); // Audio shield has SCK on pin 14
// Open serial communications and wait for port to open:
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect.
}
Serial.print("Initializing SD card...");
if (!SD.begin(chipSelect)) {
Serial.println("initialization failed!");
return;
}
Serial.println("initialization done.");
// open the file.
myFile = SD.open("test.txt", [COLOR="#FF0000"]FILE_WRITE_BEGIN);[/COLOR]
// if the file opened okay, write to it:
if (myFile) {
Serial.print("Writing to test.txt...");
myFile.println("testing 1, 2, 3.");
// close the file:
myFile.close();
Serial.println("done.");
} else {
// if the file didn't open, print an error:
Serial.println("error opening test.txt");
}
// re-open the file for reading:
myFile = SD.open("test.txt");
if (myFile) {
Serial.println("test.txt:");
// read from the file until there's nothing else in it:
while (myFile.available()) {
Serial.write(myFile.read());
}
// close the file:
myFile.close();
} else {
// if the file didn't open, print an error:
Serial.println("error opening test.txt");
}
[COLOR="#FF0000"] File root = SD.open("/");
printDirectory(root, 0); Will not display directory listing.[/COLOR]
}
void loop()
{
// nothing happens after setup
}
void printDirectory(File dir, int numSpaces) {
while(true) {
File entry = dir.openNextFile();
if (! entry) {
Serial.println("** no more files **");
break;
}
printSpaces(numSpaces);
Serial.print(entry.name());
if (entry.isDirectory()) {
Serial.println("/");
printDirectory(entry, numSpaces+2);
} else {
// files have sizes, directories do not
unsigned int n = log10(entry.size());
if (n > 10) n = 10;
printSpaces(50 - numSpaces - strlen(entry.name()) - n);
Serial.print(" ");
Serial.print(entry.size(), DEC);
DateTimeFields datetime;
if (entry.getModifyTime(datetime)) {
printSpaces(4);
printTime(datetime);
}
Serial.println();
}
entry.close();
}
}
void printSpaces(int num) {
for (int i=0; i < num; i++) {
Serial.print(" ");
}
}
void printTime(const DateTimeFields tm) {
const char *months[12] = {
"January","February","March","April","May","June",
"July","August","September","October","November","December"
};
if (tm.hour < 10) Serial.print('0');
Serial.print(tm.hour);
Serial.print(':');
if (tm.min < 10) Serial.print('0');
Serial.print(tm.min);
Serial.print(" ");
Serial.print(months[tm.mon]);
Serial.print(" ");
Serial.print(tm.mday);
Serial.print(", ");
Serial.print(tm.year + 1900);
}
